Some interconnect specifications define a power delivery protocol in which a first device advertises its power delivery capabilities (e.g., voltages and currents) to a second device. The first device thus sources power and the second device sinks power. In some implementations, the power capabilities of the source device are hard-coded in a controller internal to the source device. The source device accesses its preset configuration and advertises those particular power capabilities to the sink device. The sink selects one of the advertised power capabilities and the source device configures its power source for the agreed upon power capability.